APOD: Split the Universe (2017 Apr 01)
Re: APOD: Split the Universe (2017 Apr 01)
The Bell Inequality distinguishes between deterministic and indeterministic universes. Einstein-Podolosky-Rosen (EPR) experiments, which all use the Bell inequality, consistently show that we live in an indeterministic universe. Back in the late 1990's, I helped with an experiment by John Yukich which showed the existence of parallel universes. John did photodetachment with a pulsed laser of ions in a Penning ion trap. The laser light passed through a Michelson Interferometer before entering the trap. When the laser is well aligned through the interferometer, the interference pattern looks like a bull's eye target, with center light or dark depending on the positions of the mirrors in the interferometer. John was able to find parameters such that he had very significantly higher rates of photodetachment when it was DARK in the trap than when it was light! Each photon of light traveled one arm of the interferometer and detached an electron at one point in time, AND traveled the other arm of the interferometer and detached the SAME electron at a different point in time. When the interference for the photon was destructive, the interference for the electron was constructive, and vice versa. So he had two slightly different histories interfering. BOTH histories had to exist to get the result John Yukich observed, so at least two slightly different parallel universes exist. John Yukich is now a professor of physics at Davidson University in North Carolina.
Re: APOD: Split the Universe (2017 Apr 01)
Thanks! I just made that change. So now the APOD is really down to 0.001 sec! But then again I don't understand the & function in Javascript like I thought I did. I thought it was just the "mod" function. Is it really a "(mod + 1)" function? Or something else?Case wrote: Edit: For even/odd one could use the function (n & 1) instead of (n & 2).
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Re: APOD: Split the Universe (2017 Apr 01)
I am reminded of a hardware random number generator I built back around 1980, with a geiger tube and an americium strip from an anti-static brush. It plugged into a small computer.
Today, you can buy an assortment of computer cards that provide either quantum or classical random numbers, using a variety of internal techniques. It's a big deal for cryptography. You can also tie into random.org to get truly random numbers served, derived from atmospheric radio noise.
Today, you can buy an assortment of computer cards that provide either quantum or classical random numbers, using a variety of internal techniques. It's a big deal for cryptography. You can also tie into random.org to get truly random numbers served, derived from atmospheric radio noise.
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Re: APOD: Split the Universe (2017 Apr 01)
Something else: ‘&’ here is a so-called bitwise operator. It represents each number as a binary 32-bit signed number, then performs the AND operator on each pair of corresponding bits. The result is then converted back to (decimal) number.RJN wrote:Or something else?
Code: Select all
(1010110110)0110101001101101110100111001100 (decimal 1491246442956)
AND 0000000000000000000000000000010 (decimal 2)
= 0000000000000000000000000000000 (decimal 0)
Re: APOD: Split the Universe (2017 Apr 01)
That reminds me … the old analog tvs would display a noise pattern when not tuned to a channel. Wasn’t that mostly atmospheric noise, even partly cosmic background radiation?Chris Peterson wrote:I am reminded of a hardware random number generator I built back around 1980, with a geiger tube and an americium strip from an anti-static brush. […]You can also tie into random.org to get truly random numbers served, derived from atmospheric radio noise.
Re: APOD: Split the Universe (2017 Apr 01)
Yes, I've always thought that the "war of the ants" (as it was called in Swedish) was actually the sound of the universe?Case wrote:That reminds me … the old analog tvs would display a noise pattern when not tuned to a channel. Wasn’t that mostly atmospheric noise, even partly cosmic background radiation?Chris Peterson wrote:I am reminded of a hardware random number generator I built back around 1980, with a geiger tube and an americium strip from an anti-static brush. […]You can also tie into random.org to get truly random numbers served, derived from atmospheric radio noise.
Click to play embedded YouTube video.
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Re: APOD: Split the Universe (2017 Apr 01)
Not "atmospheric." TV frequencies pass freely through the atmosphere.Case wrote:That reminds me … the old analog tvs would display a noise pattern when not tuned to a channel. Wasn’t that mostly atmospheric noise, even partly cosmic background radiation?Chris Peterson wrote:
I am reminded of a hardware random number generator I built back around 1980, with a geiger tube and an americium strip from an anti-static brush. […]You can also tie into random.org to get truly random numbers served, derived from atmospheric radio noise.
Off channel analog TVs basically display a combination of:
- 1) 2.73 K thermal radiation from the sky and
2) ~273 K thermal radiation from the ground.
Place the TV in a metal container that totally blocks the thermal ground radiation
and you will only pick up the CBR (and win a Nobel Prize if it's not too late).
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Re: APOD: Split the Universe (2017 Apr 01)
To nitpick a bit, the pattern on TVs wasn't from the thermal radiation itself, but from the shot noise on the thermal radiation signal.neufer wrote:Off channel analog TVs basically display a combination of:
Hence ~1% of the TV pixels come from space
- 1) 2.73 K thermal radiation from the sky and
2) ~273 K thermal radiation from the ground.
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Re: APOD: Split the Universe (2017 Apr 01)
That would seem to me to be a perfectly reasonable argument to make... if I hadn't already seen (back on analog TVs) many prominent scientists make the very claim that ~1% of TV pixel noise comes from the CBR. I also know from my old NOAA job that microwave sounder instruments (which looked at high frequencies that did pick up thermal radiation from the atmosphere) were calibrated by looking at the 2.73K CBR.Chris Peterson wrote:To nitpick a bit, the pattern on TVs wasn't from the thermal radiation itself, but from the shot noise on the thermal radiation signal.neufer wrote:Off channel analog TVs basically display a combination of:
Hence ~1% of the TV pixels come from space
- 1) 2.73 K thermal radiation from the sky and
2) ~273 K thermal radiation from the ground.
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Re: APOD: Split the Universe (2017 Apr 01)
I believe that 1% of the pixel noise comes from the CBR. But it isn't the CBR signal, it's the noise on that signal. It's just a slightly sloppy way of expressing it. The concept is the same.neufer wrote:That would seem to me to be a perfectly reasonable argument to make... if I hadn't already seen (back on analog TVs) many prominent scientists make the very claim that ~1% of TV pixel noise comes from the CBR. I also know from my old NOAA job that microwave sounder instruments (which looked at high frequencies that did pick up thermal radiation from the atmosphere) were calibrated by looking at the 2.73K CBR.Chris Peterson wrote:To nitpick a bit, the pattern on TVs wasn't from the thermal radiation itself, but from the shot noise on the thermal radiation signal.neufer wrote:Off channel analog TVs basically display a combination of:
Hence ~1% of the TV pixels come from space
- 1) 2.73 K thermal radiation from the sky and
2) ~273 K thermal radiation from the ground.
In reality, I think that the actual source of the noise is probably inside the TV itself. That is, the CMB signal produces an output from the receiver, but the noise on that output is mainly the product of thermal noise in the receiver and amplifier, and not the shot noise on the signal itself. What we observe is dependent upon the existence of the CMB, but isn't a direct measure of it.
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Re: APOD: Split the Universe (2017 Apr 01)
The thermal signal from the CBR & the ground is a "noise signal"Chris Peterson wrote:
I believe that 1% of the pixel noise comes from the CBR. But it isn't the CBR signal, it's the noise on that signal. It's just a slightly sloppy way of expressing it. The concept is the same.
... and one that can be accurately measured with proper calibration.
Shot noise is really more someone has to be worried about in the optics realm:
https://en.wikipedia.org/wiki/Shot_noise wrote:
<<Shot noise is easily observable in the case of photomultipliers and avalanche photodiodes used in the Geiger mode, where individual photon detections are observed. However the same noise source is present with higher light intensities measured by any photo detector, and is directly measurable when it dominates the noise of the subsequent electronic amplifier.>>
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Re: APOD: Split the Universe (2017 Apr 01)
No, it isn't. Aim a microwave receiver at the sky and you'll see the CMB signal- a blackbody curve peaking at a wavelength of around 2mm. In a noiseless system, this would simply produce a uniform background intensity on a TV screen. The snow is the product of noise on this signal- either shot noise on the signal itself, or noise inside the TV electronics superimposed on the DC signal.neufer wrote:The thermal signal from the CBR & the ground is a "noise signal"Chris Peterson wrote: I believe that 1% of the pixel noise comes from the CBR. But it isn't the CBR signal, it's the noise on that signal. It's just a slightly sloppy way of expressing it. The concept is the same.
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Re: APOD: Split the Universe (2017 Apr 01)
Chris Peterson wrote:No, it isn't. Aim a microwave receiver at the sky and you'll see the CMB signal- a blackbody curve peaking at a wavelength of around 2mm. In a noiseless system, this would simply produce a uniform background intensity on a TV screen. The snow is the product of noise on this signal- either shot noise on the signal itself, or noise inside the TV electronics superimposed on the DC signal.neufer wrote:The thermal signal from the CBR & the ground is a "noise signal"Chris Peterson wrote:
I believe that 1% of the pixel noise comes from the CBR. But it isn't the CBR signal, it's the noise on that signal. It's just a slightly sloppy way of expressing it. The concept is the same.
- Well...let's just look it up:
https://en.wikipedia.org/wiki/Noise_(video) wrote: <<Noise, in analog video and television, is a random dot pixel pattern of static displayed when no transmission signal is obtained by the antenna receiver of television sets and other display devices. The random pattern superimposed on the picture, visible as a random flicker of "dots" or "snow", is the result of electronic noise and radiated electromagnetic noise accidentally picked up by the antenna. This effect is most commonly seen with analog TV sets or blank VHS tapes.
There are many sources of electromagnetic noise which cause the characteristic display patterns of static. Atmospheric sources of noise are the most ubiquitous, and include electromagnetic signals prompted by cosmic microwave background radiation, or more localized radio wave noise from nearby electronic devices.
The display device itself is also a source of noise, due in part to thermal noise produced by the inner electronics. Most of this noise comes from the first transistor the antenna is attached to.
UK viewers used to see "snow" on black after sign-off, instead of "bugs" on white, a purely technical artifact due to old 405-line British senders using positive rather than the negative video modulation used in Canada, the U.S., and (currently) the UK as well. Since one impression of the "snow" is of fast-flickering black bugs on a white background, the phenomenon is often called myrornas krig in Swedish, myrekrig in Danish, hangyák háborúja in Hungarian, and semut bertengkar in Indonesian, which all translate to "war of the ants". It is also known as karıncaların filmi in Turkish, meaning "film/movie of ants," hangyafoci in Hungarian which means "ant soccer", and in Romanian, purici, which translates into "fleas".
Due to the algorithmic functioning of a digital television set's electronic circuitry and the inherent quantization of its screen, the "snow" seen on digital TV is less random. Most modern televisions automatically change to a blue screen or turn to standby after some time if static is present.>>
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Re: APOD: Split the Universe (2017 Apr 01)
In other words, exactly what I said.neufer wrote:Chris Peterson wrote:No, it isn't. Aim a microwave receiver at the sky and you'll see the CMB signal- a blackbody curve peaking at a wavelength of around 2mm. In a noiseless system, this would simply produce a uniform background intensity on a TV screen. The snow is the product of noise on this signal- either shot noise on the signal itself, or noise inside the TV electronics superimposed on the DC signal.neufer wrote: The thermal signal from the CBR & the ground is a "noise signal"
- Well...let's just look it up:
https://en.wikipedia.org/wiki/Noise_(video) wrote: <<Noise, in analog video and television, is a random dot pixel pattern of static displayed when no transmission signal is obtained by the antenna receiver of television sets and other display devices. The random pattern superimposed on the picture, visible as a random flicker of "dots" or "snow", is the result of electronic noise and radiated electromagnetic noise accidentally picked up by the antenna. This effect is most commonly seen with analog TV sets or blank VHS tapes.
There are many sources of electromagnetic noise which cause the characteristic display patterns of static. Atmospheric sources of noise are the most ubiquitous, and include electromagnetic signals prompted by cosmic microwave background radiation, or more localized radio wave noise from nearby electronic devices.
The display device itself is also a source of noise, due in part to thermal noise produced by the inner electronics. Most of this noise comes from the first transistor the antenna is attached to.
UK viewers used to see "snow" on black after sign-off, instead of "bugs" on white, a purely technical artifact due to old 405-line British senders using positive rather than the negative video modulation used in Canada, the U.S., and (currently) the UK as well. Since one impression of the "snow" is of fast-flickering black bugs on a white background, the phenomenon is often called myrornas krig in Swedish, myrekrig in Danish, hangyák háborúja in Hungarian, and semut bertengkar in Indonesian, which all translate to "war of the ants". It is also known as karıncaların filmi in Turkish, meaning "film/movie of ants," hangyafoci in Hungarian which means "ant soccer", and in Romanian, purici, which translates into "fleas".
Due to the algorithmic functioning of a digital television set's electronic circuitry and the inherent quantization of its screen, the "snow" seen on digital TV is less random. Most modern televisions automatically change to a blue screen or turn to standby after some time if static is present.>>
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Re: APOD: Split the Universe (2017 Apr 01)
Chris Peterson wrote:
In other words, exactly what I said.
- Not exactly.
The Wikipedia article seems to be saying that the "ants" represent
the antenna thermal pickup plus some unquantified internal TV noise.
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Re: APOD: Split the Universe (2017 Apr 01)
Whatever. The point is that the snow is probably not made up of either the CMB or thermal noise from the Earth.neufer wrote:Chris Peterson wrote:
In other words, exactly what I said.You seem to be saying that the antenna thermal pickup contributes only to the overall gray of the screen while the "ants" represent the random internal TV noise.
- Not exactly.
The Wikipedia article seems to be saying that the "ants" represent
the antenna thermal pickup plus some unquantified internal TV noise.
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Re: APOD: Split the Universe (2017 Apr 01)
Chris Peterson wrote:
Whatever. The point is that the snow is probably not made up of either the CMB or thermal noise from the Earth.
https://en.wikipedia.org/wiki/Noise_(video) wrote:
<<The random pattern superimposed on the picture, visible as a random flicker of "dots" or "snow", is the result of electronic noise and radiated electromagnetic noise accidentally picked up by the antenna [including] electromagnetic signals prompted by cosmic microwave background radiation.>>
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Re: APOD: Split the Universe (2017 Apr 01)
Yes. Which does not mean we are seeing any noise from the CMB.neufer wrote:Chris Peterson wrote:
Whatever. The point is that the snow is probably not made up of either the CMB or thermal noise from the Earth.https://en.wikipedia.org/wiki/Noise_(video) wrote:
<<The random pattern superimposed on the picture, visible as a random flicker of "dots" or "snow", is the result of electronic noise and radiated electromagnetic noise accidentally picked up by the antenna [including] electromagnetic signals prompted by cosmic microwave background radiation.>>
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Re: APOD: Split the Universe (2017 Apr 01)
This topic once was thoughtful and important, dealing with the age old free will vs determinism debate, but then it got drowned out by noise. ![Confused :?](./images/smilies/icon_confused.gif)
![Confused :?](./images/smilies/icon_confused.gif)
Just as zero is not equal to infinity, everything coming from nothing is illogical.
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Re: APOD: Split the Universe (2017 Apr 01)
Cosmic noise, though.BDanielMayfield wrote:This topic once was thoughtful and important, dealing with the age old free will vs determinism debate, but then it got drowned out by noise. :?
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Re: APOD: Split the Universe (2017 Apr 01)
Suppose it isn't pigeon poop either… ![No. :no:](./images/smilies/no.gif)
![No. :no:](./images/smilies/no.gif)
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Re: APOD: Split the Universe (2017 Apr 01)
Joe Rudmin wrote:The Bell Inequality distinguishes between deterministic and indeterministic universes. Einstein-Podolosky-Rosen (EPR) experiments, which all use the Bell inequality, consistently show that we live in an indeterministic universe.
I like this, and it seems most logical too, for both micro and macro things. Just as the time when an individual unstable atom will decay cannot be precisely predicted, nether can the exact actions of people be predicted.
Personally I've viewed the multi-universe notions as redundant, unnecessary, unproven and unprovable, so what Joe Rudman wrote here was eye opening. Still, this micro result does not infer that an infinity of macro universes exist.Back in the late 1990's, I helped with an experiment by John Yukich which showed the existence of parallel universes. John did photodetachment with a pulsed laser of ions in a Penning ion trap. The laser light passed through a Michelson Interferometer before entering the trap. When the laser is well aligned through the interferometer, the interference pattern looks like a bull's eye target, with center light or dark depending on the positions of the mirrors in the interferometer. John was able to find parameters such that he had very significantly higher rates of photodetachment when it was DARK in the trap than when it was light! Each photon of light traveled one arm of the interferometer and detached an electron at one point in time, AND traveled the other arm of the interferometer and detached the SAME electron at a different point in time. When the interference for the photon was destructive, the interference for the electron was constructive, and vice versa. So he had two slightly different histories interfering. BOTH histories had to exist to get the result John Yukich observed, so at least two slightly different parallel universes exist. John Yukich is now a professor of physics at Davidson University in North Carolina.
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Re: APOD: Split the Universe (2017 Apr 01)
However, indeterminate does not mean not determined. The entire state of the Universe from its beginning to infinitely far in the future may be determined, set in stone, and still entirely indeterminate.BDanielMayfield wrote:Joe Rudmin wrote:The Bell Inequality distinguishes between deterministic and indeterministic universes. Einstein-Podolosky-Rosen (EPR) experiments, which all use the Bell inequality, consistently show that we live in an indeterministic universe.
I like this, and it seems most logical too, for both micro and macro things. Just as the time when an individual unstable atom will decay cannot be precisely predicted, nether can the exact actions of people be predicted.
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Re: APOD: Split the Universe (2017 Apr 01)
I can readily accept that. Many divergent paths can eventually converge to the same outcome.Chris Peterson wrote:However, indeterminate does not mean not determined. The entire state of the Universe from its beginning to infinitely far in the future may be determined, set in stone, and still entirely indeterminate.BDanielMayfield wrote:Just as the time when an individual unstable atom will decay cannot be precisely predicted, nether can the exact actions of people be predicted.
But let's focus on the here and now. Each of us as thinking organisms exercise free will all the time whenever we make decisions. We are not like preprogrammed robots hiding in organic bodies. Otherwise, concepts like freedom would be mere illusions.
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Re: APOD: Split the Universe (2017 Apr 01)
Perhaps, but that's not what I meant. I meant that the Universe in 4 dimensions could be static from an "outside" view, but completely unpredictable from any point along any path. More formally, that every worldline exists from the moment of its creation to the end of time, but from any point along the worldline it is impossible to predict what the future portion of that line looks like. Determined, but not deterministic.BDanielMayfield wrote:I can readily accept that. Many divergent paths can eventually converge to the same outcome.Chris Peterson wrote:However, indeterminate does not mean not determined. The entire state of the Universe from its beginning to infinitely far in the future may be determined, set in stone, and still entirely indeterminate.BDanielMayfield wrote:Just as the time when an individual unstable atom will decay cannot be precisely predicted, nether can the exact actions of people be predicted.
I've never encountered a definition of "free will" that was sufficiently clear or coherent for me to make sense of what an assertion like the one you make here even means.But let's focus on the here and now. Each of us as thinking organisms exercise free will all the time whenever we make decisions. We are not like preprogrammed robots hiding in organic bodies. Otherwise, concepts like freedom would be mere illusions.
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